Portable power driven saw



y 1961 H. w. BORK 2,993,518

PORTABLE POWER DRIVEN SAW Original Filed March 51, 1958 2 Sheets-Sheet 136 INVENTOR.

July 25, 1961 H. w. BORK 2,993,518

PORTABLE POWER DRIVEN SAW Original Filed March 31, 1958 2 Sheets-Sheet 2I I V 7 IN VENTOR.

to the user if a knot is struck or the saw is overloaded in green wood.For these reasons, clutch devices of various kinds have become common sothat the blade can be stopped while the arbor continues to turn, thuseliminating kick-back to a great extent. These clutch devices make bladechanging most ditficult, however, as the blade can be clamped by nail asset forth above but a wrench on a tight saw stud will merely turn thearbor with respect to the blade and will not loosen the stud from thearbor.

To overcome these difliculties and for safety to the operator, applicanthas provided the arbor locking plate 18 splined or otherwise positivelyattached to arbor 13 for rotation therewith.

Locking plate 18 (FIG. 6) is formed with a plurality of locking socketsor notches 50 on its perimeter to selectively receive a lock pin 52 thatis normally yieldingly held out of engagement with the notches by acompression spring 54. Lock pin 52 is slidably mounted in the wall ofhousing and a suitable bearing member 56. spaced therefrom in thehousing. It extends outwardly beyond the wall of housing 10 to form athumb portion 58 and at its other end 60 is adapted to be pressed into alocking notch 50.

.At its outer end, but within the housing 10, lock pin 52 may have aroller stop pin 55 mounted therein that forms a seat for spring 54 atone end While the spring may be seated against bearing member 56 at itsother end.

From this description it will be understood that when an operator wishesto remove a saw blade 21, he will press in on lock pin 52 and apply asuitable wrench to saw stud 23. If no locking notch is immediately inplace to receive pin 52, a slight turn of the stud and arbor will bringone into locking relationship. Regardless of the presence of a bladeclutch or not, the arbor is locked against rotation and the stud may beremoved without trouble.

I claim:

1. In a portable power driven saw the combination with a housing, arotatable power driven arbor mounted therein and a saw blade mountableon said arbor at least in part by a threaded member, of a locking platewithin said housing mounted on said arbor for rotation therewith andhaving a plurality of locking notches in its periphery, a radiallyextending lock pin slidably mounted on said housing and spring biased topresent a portion to normally extend outwardly of said housing, said pinbeing yieldably pressable into locking engagement with one of saidlocking notches whereby to lock said arbor against rotation whileturning said threaded member.

2. In a portable power driven saw the combination with a housing, arotatable power driven arbor mounted therein and a saw blade mountableon said arbor at least in part by a threaded member, of means forlocking said arbor against rotation while turning said threaded member,said means including a locking plate mounted on said arbor for positiverotation therewith and having locking notches therein, complementarylocking means on said housing presenting a portion to engage saidlocking plate, said locking means being accessible from the exterior ofsaid housing, said locking means and said'plate being thereby adapted tobe interengaged to prevent rotation of said plate and arbor.

3. In a portable power driven saw the combination with ahousing, arotatable power driven arbor mounted therein and a saw blade mountableon said arbor at least in part by a threaded member, of means forlocking said arbor against rotation while turning said threaded member,said means including a locking plate positively mounted on said arborfor rotation therewith, a plurality of spaced locking sockets in saidplate, a locking pin slidably mounted on said housing adjacent saidplate and adapted to be slid into and out of locking engagement with oneof said locking sockets, a portion of said pin extending exteriorly ofsaid housing when out of locking engagement and yielding means biasingsaid pin out of said locking engagement.

References Cited in the file of this patent UNITED STATES PATENTS741,034 Hazelton Oct. 13, 1903 1,400,614 Lovejoy Dec. 20, 1931 1,848,330Emmons Mar. 8, 1932 1,900,553 Hampton Mar. 7, 1933

